994 resultados para 800.85
Resumo:
在全球变化背景下,森林生态系统CO2和H2O交换过程已经成为国际研究的前沿问题。本研究以长白山阔叶红松林为研究对象,利用基于生理生态学过程的多层模型,考虑了混交林中不同树种的生物量、冠层高度和厚度,对冠层及生态系统尺度的碳水通量进行了详细模拟及分析,同时用涡动相关实测数据对模拟结果进行检验,并模拟和预测了阔叶红松林生态系统碳水收支对气候变化的响应,以期为我国研究区域甚至更大尺度碳水平衡的时间和空间格局特征提供模型储备。本文的主要结论如下: 1)长白山阔叶红松林主要优势树种红松、紫椴、水曲柳、色木槭和蒙古栎的生理生态学参数(初始量子效率α、光饱和时的最大净光合作用速率Pmax、最大Rubisco催化反应速率Vcmax、CO2饱和时的最大净光合作用速率Jmax)有着明显且不同的季节变化。6、8月的α值较大,Pmax、Vcmax和Jmax的最大值也出现在6—8月,而5、9月的各项参数值均较小。 2)对阔叶红松林冠层结构的观测,发现各树种在冠层中所处位置有明显差异。假设各树种水平分布均匀,以各树种的冠高、冠厚和叶片生物量为依据,将冠层垂直分为20层,模拟出各层各树种的CO2和H2O通量。这与传统的假设各树种垂直均匀分布相比,更加符合阔叶红松林的实际群落结构。 3)长白山阔叶红松林的能量平衡比EBR为0.800,居于国际同类观测的中上水平,涡相关观测数据较为可靠。CO2和H2O通量有明显日变化,夜间值较小且变化平缓,白天值呈单峰形的日变化。对2003—2007年生长季的模拟结果分析表明,CO2和H2O通量模拟值与涡相关实测值的回归线斜率分别为0.935和0.875,截距为-0.0136 mg•m-2•s-1和13.7 W•m-2,相关系数为0.655和0.622(n=30107);CO2通量模拟和实测的平均值分别为-0.138和-0.134 mg•m-2•s-1,模型高估了2.99%;H2O通量模拟和实测的平均值分别为88.5和85.4 W•m-2,模型高估了3.63%,模拟效果较好。从季节变化来看,生长季初、末期(5月和9月)CO2和H2O通量较小,生长旺盛期(6—8月)通量值较高。CO2和H2O通量受环境因子的综合影响,其中,辐射和气温是主要限制因子。 4)对模型的主要参数和环境因子的敏感性分析表明,CO2通量对a1 (气孔导度的参数)、Vcmax、Ca (大气CO2浓度)变化的响应较强,而H2O通量对a1、LAI (叶面积指数)、Ta (气温)变化的响应较强。CO2通量对Ca的变化最为敏感,而H2O通量对其它环境因子的响应程度均高于CO2通量。与将冠层分为20层的方法相比,5层方法(Gaussion五点积分法)得到的碳吸收量和蒸发散量分别低估了25.3%和11.1%。这两种分层方法产生的差异,主要来自于不同层的辐射吸收和权重分配。
Resumo:
利用102MeV的28Si束流,通过60Ni(28Si,2pn)熔合蒸发反应布居了85Zr核的高自旋态,测量了γ-γ符合及DCO比值,建立了一个有43条能级,75条γ跃迁的能级纲图,新增加了36条γ跃迁,25条能级.将能级自旋推高到(49/2+),首次观察到了转晕带的第二回弯.并确认了一条建立在17/2-负宇称带上的磁转动带.
Resumo:
介绍了近代物理研究所自行研制的新型HIRFL 80 0低温泵。对其抽速、低温冷凝板和屏蔽板的热负荷进行了具体的分析和计算。肯定了新型HIRFL 80 0低温泵的设计方案
Resumo:
<正>质量数80区的过渡性核表现了集体性和单粒子性的能级结构。对质子数Z为37~40、中子数N=45的原子核,如81Kr,87Mo核,在中低自旋时显示了单粒子特性,而在高自旋态时表现出较多的集体性。 近些年来,在过渡区在束γ谱学,如83Rb、83Y等核研究中,观察到了一串建立在较高K态的增强的△I=1的M1跃迁。它被认为是一种新的激发模式,叫做磁转动带。我们对85Zr的研究目的,一是将其能级推到更高自旋,另一个是寻找该核的磁转动带。
Resumo:
本论文首先介绍真空技术涉及的物理基础和真空获得的有关知识,然后讲述,了H_RFL(兰州重离子加速器研究装置)真空系统的基本概况,在此基础上阐述了本论文主要的两部分:H_RFL前束线真空系统的改造;新型H_RFL佩800低温泵的设计一及热负荷的计算。其中H工RF[前束线真空系统的改造已经于2001年9月份完成并为兰州重离子加速器的正常运行提供了必要的真空条件。新型111佩又FL佩800低温泵正在加工生产中,并将用于大型超高真空系统H工R凡厂SSC(兰州重离子加速器研究装置主加速器)的抽空。H工RFL前束线真空系统的改造介绍了兰州重离子加速器前束线真空系统的基本结构,详细说明了H工RFL前束线真空系统改造前的流导、气体负荷及压力分布情况。提出了具体的改造措施。真空系统达到了预计要求:泵口压强小于5只10-6Pa,两泵之间束运管道中心平面压强小于1x10-5Pa.结果表明H工RFL前束线真空系统的改造方案是有效的。新型HIRFL一800低温泵的设计及热负荷的计算介绍了近代物理研究所自行研制的新型H工RFL一800低温泵。对其抽速,低温冷凝板和屏蔽板的热负荷进行了具体的分析和计算。肯定了新型H工RFL佩800低温泵的设计方案。
Resumo:
在实验室内进行了虎杖(Polygonum cuspidatum Sieb.etZucc.)根提取物及其活性组分分离研究,并且对黄瓜白粉病进行了活性测定及温室小区试验。结果表明,无论提取率还是作用效果,乙醇较适合于做为虎杖根提取物的提取溶剂。虎杖根乙醇提取物和乙醚提取物对黄瓜白粉病的EC90值分别为537.85、35.38mg/L,而乙醚提取后残留物的活性很弱,说明乙醇提取物中具有杀菌作用的成分主要存在于乙醚提取物中。用pH梯度分离法对乙醚提取物进行分离,得到3个不同组分,其中以氢氧化钠分离得到的组分对黄瓜白粉病显示了极高的杀菌活性。在温室条件下虎杖乙醇提取物在800~1600mg/L下对黄瓜白粉病的防效相当或优于对照药剂三唑酮。
Resumo:
Numerous cores and dating show the Yangtze River has accumulated about 1.16 x 10(12) t sediment in its delta plain and proximal subaqueous delta during Holocene. High-resolution seismic profiling and coring in the southern East China Sea during 2003 and 2004 cruises has revealed an elongated (similar to 800 km) distal subaqueous mud wedge extending from the Yangtze River mouth southward off the Zhejiang and Fujian coasts into the Taiwan Strait. Overlying what appears to be a transgressive sand layer, this distal clinoform thins offshore, from similar to 40 in thickness between the 20 and 30 m water depth to < 1-2 in between 60 and 90 m water depth, corresponding to an across shelf distance of less than 100 km. Total volume of this distal mud wedge is about 4.5 x 10(11) m(3), equivalent to similar to 5.4 x 10(11) t of sediment. Most of the sediment in this mud wedge comes from the Yangtze River, with some input presumably coming from local smaller rivers. Thus, the total Yangtze-derived sediments accumulated in its deltaic system and East China Sea inner shelf have amounted to about 1.7 x 10(12) t. Preliminary analyses suggest this longshore and across-shelf transported clinoform mainly formed in the past 7000 yrs after postglacial sea level reached its mid-Holocene highstand, and after re-intensification of the Chinese longshore current system. Sedimentation accumulation apparently increased around 2000 yrs BP, reflecting the evolution of the Yangtze estuary and increased land erosion due to human activities, such as fanning and deforestation. The southward-flowing China Coastal Current, the northward-flowing Taiwan Warm Current, and the Kuroshio Current appear to have played critical roles in transporting and trapping most of Yangtze-derived materials in the inner shelf, and hence preventing the sediment escape into the deep ocean. (c) 2006 Elsevier B.V. All rights reserved.
Resumo:
本论文在FPS研究的基础上,结合中医配伍理论,研究将FPS与几味传统中药-大黄、黄芪、泽泻、益母草的提取物组合成治疗慢性肾功能衰竭的海洋复方新药物。由于FPS研究相对成熟,故对复方药物中FPS外其它组分(以下简称复方)的提取、分离工艺以及制定复方质量的标准和检测方法等药学内容进行研究,为下一步新药的开发打下基础。 1. 对复方的醇提与水提进行了比较,确定了复方最佳提取方法-醇提。采用正交实验设计方法对醇提工艺进行优化,以复方中主要有效成分的含量为指标进行综合评价,得到了复方提取的最佳工艺:8倍量95%乙醇回流提取两次,1.5h/次,并对该提取工艺进行了验证实验,结果表明本工艺提取物中各主要有效成分的含量均较高,是可靠可行的。 2. 采用微波水提法,对复方中的单味药-黄芪的主要有效成分黄芪皂苷的提取进行了研究,通过正交实验设计方法优选出了最佳提取工艺为20倍量水、微波功率800 W、对60目黄芪提取两次、15 min/次。将该工艺与传统乙醇回流提取方法进行了对比,结果表明该工艺快速、经济、有较好的皂苷提取率,是黄芪皂苷提取的很好的方法。 3. 进行缺FPS的褐藻糖含量测定阴性对照实验,结果阴性无干扰,褐藻糖含量测定可以作为控制复方质量的一个指标。分别做缺大黄和缺黄芪阴性对照实验,结果总蒽醌和总皂苷含量测定阴性干扰较大,大黄素含量测定阴性无干扰,确定大黄素含量测定为控制复方质量的另一指标。 4. 进行复方提取物质量控制指标之一-大黄素含量测定的分析方法学研究,找到了一稳定可行的方法-HPLC方法,该方法测定条件为:流动相甲醇与0.1%磷酸比例为85:15,柱温40℃,通过ODS柱分离,用二极管阵列检测器在436 nm下测定含量。该方法测定复方提取物中大黄素含量精密度高、专一性好、干扰小,可用来控制复方的质量。
Resumo:
The Stack Spontaneous Potential (SSP) is a direct hydrocarbon location technology and a new hydrocarbon detection method with independent intellectual property. A subsurface hydrocarbon accumulation associated with the upward hydrocarbon micro seepage induces a relatively strong negative potential abnormal zone, of which the anomaly can be measured on the surface with specially designed instruments through careful field measuring procedures. With special software programmed according to a unique geochemical and geophysical model, the original data are analyzed, processed and interpreted on the computer, and then on a series of resulting anomaly distribution maps and/or profiles, the favorable surface locations of the hydrocarbon accumulations can be easily identified. The study of the SSP has been started since 1989, and especially from 1996 to 1997, both profile and area tests were conducted in the Daqing Oilfield. On the testing line of 15kms, there are 6 wells in total, among which some are oil-producing wells, and some are water-producing wells. The final matching ratio of the favorable oil well locations and the possible water well locations predicted by the SSP to those of known wells was up to 83 percent. In the area test, of which the acreage is 800 km2, the matching ratio compared with the existing wells was 87 percent; furthermore, regarding to wells subsequently drilled after the test, the matching ratio was 85 percent. The matching ratio in the development area is more about 10 percent than those of in exploration area. The reason is that, comparing the exploration area, the development area acreage is less and the container rocks are more simplex. In development area there is not so much interference of SSP also. Since 1997 the SSP has been tested and applied all over China to a number of hydrocarbon bearing basins and known oil fields, including the Daqing, Jiangsu, Changqing, Shengli, Nanyang, Jianghan and Zhongyuan Oilfields, only to name a few. The SSP surveys in total areas of over 10,000km2 in more than 30 regions in China so far have been completed in various exploration and development stages, the satisfactory outcomes of which have further evidenced that the dependence between the SP anomaly and abundance of hydrocarbon. Up to date, a substantial amount of successful tests and actual surveys finished in exploration and development practices have evidenced that the SSP is significantly more reliable in comparison with any other similar direct hydrocarbon indication technique generally known to the oil industry, such as the Redox. The SSP can be applied to search for almost all kinds of hydrocarbon accumulations, regardless of the type of traps, such as structural, stratigraphic, buried hill traps, and so on; however, it is interesting to be noted that the SSP seems to be particularly effective in detecting the stratigraphic oil traps according to our practices. On the other hand, there is virtually no surface geographical constrains in terms of field data acquisition, except for those water covered areas, because of the inherent characteristics of the technology itself. Furthermore, utilizing the SSP requires no special considerations to subsurface geological conditions in regard to formation resistivity, since the SSP measurements will not be influenced by either overly high or overly low resistivity of formations lying above the hydrocarbon accumulations. There are two kind of theory, of which, as we know one is called hypbyssal theory such as "Redox"[61 the other is call plutonic theory such as cracking of hydrocarbon [8][9] and natural polarization [3], to describe the mechanism of SP anomaly of oil reservoir and to indicate that the dependence between the SP abnormality and abundance of hydrocarbon has be existed theoretically/The quantitative dependence, which has not been founded due to the complicity of container rocks, be discovered during the exploration and development practices is the crux to the quantitative analysis of SP Anomaly processing. Based on the thorough study of the complex of collector rocks, every kind of thickness of collector rock can be conversed to be a standard effective thickness; the thickness is called apparent effective thickness (AET). The conversation coefficient (ai, 1=1,2,3) could be determined by the variety of every collector rock storability (CRS). The discoveration of quantitative: dependence between AET and the amplitude of SSP, in the practices of exploration and development, is a promotion for the SSP supplied in the oil exploration, and make the data analysis forward to the quantitative stage.
Resumo:
1985